15.2.2 Water source identification
All potential water sources should be considered and checked. Issues to consider are the sources of possible contaminants, the amount of water available to users annually and the consistency of the supply. Other important issues are social acceptance, cost effectiveness and community health. All potential water sources need to be assessed in order to identify the best solution.
For instance, whenever rivers and streams are considered for use and development, the communities immediately upstream and downstream should be consulted and involved in the decision-making process prior to implementation. This is because both quality and quantity of surface water can be affected by the activities of the people living upstream (toward the source of the stream or river). If the upstream users abstract large volumes or pollute the water, this will have a damaging effect on the downstream users (Figure 15.4). All communities have an interest in having good quality and adequate quantities of water; therefore, it is important that proposed surface water developments should be discussed with and agreed by both the upstream and downstream communities.